Cargo container

ABSTRACT

A container for transporting goods by airplane comprises a top wall, a bottom wall, and a pair of opposed side walls all bounded by rigid framework and cooperating to define a pair of openings which are respectively closed by stowable door structures, each of the door structures including a pair of door brackets pivotally mounted on the top wall framework and two hingedly interconnected door panels one of which is slidably mounted on the door brackets, the door structures being movable between a closed position completely closing the openings and a stowed position folded atop the container, and two latch assemblies on each door structure for holding it in the closed position; adjustable shelves are mounted on the framework within the container.

United States Patent Feddersen et al.

1 1 June 27, 1972 [54] CARGO CONTAINER [72] lnventors: Donald W.Feddersen, Northbrook; Everett L. Markowski, Morton Grove, both of Ill.

[73] Assignee: Air Cargo Equipment Corporation, Tulsa,

Okla.

[22] Filed: Nov. 14, 1969 [21] Appl. No.: 876,654

[52] U.S.Cl ..220/1.5, 16/179, 49/197, 220/34, 220/38, 220/84, 292/281[51] lnt.Cl ..B65d 87/00 [58] Field of Search ..312/215, 286, 263, 264,352, 312/333; 220/1.5, 38, 34, 84; 160/113, 117, 118, 206, 207, 213;292/281; 49/197, 201, 202; 16/179 [56] References Cited UNITED STATESPATENTS 1,273,838 7/1918 Fairhurst ..160/118 UX 1,854,125 4/1932 Faber..292/281 UX 2,200,277 5/1940 Howie ..220/1.5 X 2,909,220 10/1959Zimmerman ....,l60/2l3 3,260,561 7/1966 Traktman.... .....3l2/2643,221,803 12/1965 Lambert... .....160/206 3,240,545 3/1966 Rulf..312/264 3,419,164 12/1968 ONeill ..220/1.5X 2,241,884 5/1941 Noble..220/38 X Primary Examiner-Joseph R. Leclair Assistant Examiner-JamesR. Garrett Attorney-Prangley, Clayton, Mullin, Dithmar & Vogel [5 7]ABSTRACT A container for transporting goods by airplane comprises a topwall, a bottom wall, and a pair of opposed side walls all bounded byrigid framework and cooperating to define a pair of openings which arerespectively closed by stowable door structures, each of the doorstructures including a pair of door brackets pivotally mounted on thetop wall framework and two hingedly interconnected door panels one ofwhich is slidably mounted on the door brackets, the door structuresbeing movable between a closed position completely closing the openingsand a stowed position folded atop the container,

and two latch assemblies on each door structure for holding it in theclosed position; adjustable shelves are mounted on the framework withinthe container.

38 Claims, 39 Drawing Figures PATENTEDJUMN I972 3. 672 529 SHEET D8 or12 236 I 23 7 23Ar lag-C r v 253 PATENTEDJum I972 sum as or 12PATENTEDJum I972 SHEET 12 0F 12 CARGO CONTAINER This invention isdirected to a container for use in an airplane, the container beingconstructed to be lightweight and compact, yet durable.

It is an important object of the present invention to provide in acontainer having a top wall and a bottom wall and a pair of opposed sidewalls all cooperating to define a door-receiving opening, a doorstructure comprising a door bracket pivotally mounted on the containeradjacent to the door-receiving opening, and a door panel shapedcomplementary to the opening and slidably mounted on the door bracketand movable between an extended condition and a retracted conditionthereon, the door bracket being movable between a closed positionwherein the door panel is disposed within the doorreceiving opening andsubstantially normal to an adjacent wall of the container and an openposition wherein the door panel is disposed outside of the container andsubstantially parallel to the adjacent wall thereof, the door structurehaving a closed position wherein the door bracket is in the closedposition thereof and the door panel is in the extended condition thereofwhereby the door structure completely closes the door-receiving opening,the door structure having a stowed position wherein the door bracket isin the open position thereof and the door panel is in the retractedcondition thereof whereby the door structure is completely removed fromthe door-receiving opening and the door panel is stowed alongside theadjacent one of the container walls substantially parallel thereto.

In connection with the foregoing object, yet another object of thisinvention is to provide a door structure of the type set forth whereinthe door bracket has a first track member thereon and the door panel hasa second track member thereon cooperating with the first track memberfor slidably mounting the door panel on the door bracket.

In connection with the foregoing object, still another object of thisinvention is to provide a door structure of the type set forth andfurther including an abutment flange carried by the adjacent one of thecontainer walls and disposed adjacent to the opening and contacting thedoor bracket in the open position thereon for limiting the pivotalmovement thereof in the opening direction.

in connection with the foregoing object, it is yet another object ofthis invention to provide a door structure of the type set forth whichincludes a hook member carried by the door panel adjacent to the topwall and engageable in the flange when the door bracket is in the closedposition thereof and the door panel is in the extended condition thereoffor supporting the door panel and limiting the sliding movement thereofin the extending direction.

It is another object of this invention to provide a door structure ofthe type set forth which further includes a retaining member carried bythe door panel and engageable with the container when the door structureis in the closed position thereof for preventing pivotal movementthereof, and resilient latch stnicture carried by the door panel andengageable with the container for holding the door panel in the extendedcondition thereof to hold the retaining member in engagement with thecontainer, whereby the retaining member cooperates with the latchstructure to hold the door structure in the closed position thereof.

In connection with the foregoing object, another object of thisinvention is to provide a door structure of the type set forth includinga keeper structure mounted on the container and extending through acomplementary opening in the door panel when the door structure is inthe closed position thereof to maintain the door panel in the extendedcondition thereof, and a latch mechanism resiliently mounted on theouter surface of the door panel and movable into and out of engagementwith the keeper structure when the door structure is in a closedposition thereof.

In connection with the foregoing objects, it is a further object of thisinvention to provide a door structure of the type set forth whichincludes a first door panel shaped complementary to a portion of thedoor-receiving opening and slidably mounted on the door bracket andmovable between an extended condition and a retracted condition thereon,and a second door panel shaped complementary to the remaining portion ofthe door-receiving opening and hingedly connected to the first doorpanel and being pivotally movable between a first position substantiallyin alignment with the first door panel and a second position overlyingthe first door panel and substantially parallel thereto, the second doorpanel being in the second position thereof when the door structure is inthe stowed position thereof whereby the door panels are stowed alongsidethe adjacent one of the container walls substantially parallel thereto.

It is another object of this invention to provide a container comprisinga top wall and a bottom wall and a pair of opposed side walls allcooperating to define an opening into the container, a plurality ofshelf support members mounted on the container and each disposedsubstantially normal to one of the walls and each having a plurality ofaligned spaced apertures therein, a shelf insertable into the containerin a predetermined direction through the opening therein and having amounted position substantially parallel to the one wall with an edge ofthe shelf disposed toward the opening, a fixed pin carried by the shelfon another edge thereof and disposed in use adjacent to one of thesupport members and insertable into a selected one of the aperturestherein, a movable pin carried by the shelf on an edge other than theanother edge and disposed in use adjacent to another of the supportmembers and movable into a selected one of the apertures therein, themovable pin having a retracted position wherein it is disposed out ofthe apertures of the adjacent support member and an extended positionwherein it is disposed in one of the apertures therein, the fixed pinand the movable pin in the extended position thereof having thelongitudinal axes thereof angularly disposed with respect to each other,the shelf with the movable pin in the retracted position thereof beinginsertable into the container in the predetermined direction through theopening to insert the fixed pin into the selected one of the aperturesin the associated support member to place the shelf in the mountedposition thereof, the movable pin thereafter being movable from theretracted position thereof into the extended position thereof and intothe one aperture in the associated member fixedly to lock the shelf inthe mounted position thereof upon the support members within thecontainer.

in connection with the foregoing object, still another object of thisinvention is to provide a container of the type set forth having asubstantially rectangular top wall and including at least four shelfsupport members respectively disposed adjacent to the edges of the topwall, the shelf including a movable pin carried by the shelf on thefront edge thereof and disposed in use adjacent to an associated one ofthe support members and movable into a selected one of the aperturestherein and at least three fixed pins respectively carried by the shelfon the other edges thereof and respectively disposed in use adjacent toassociated ones of the support members and respectively insertable intoselected ones of the apertures therein.

In connection with the foregoing object, a still further object of thisinvention is to provide a shelf of the type set forth adapted for use ina container of the type set forth.

It is another object of this invention to provide in a container havinga top wall and a bottom wall and a pair of opposed side walls allcooperating to define a pair of doorreceiving openings at the oppositeends of the container, two door structures of the type set forth forrespectively closing the door-receiving openings.

Yet another object of this invention is to provide a containercomprising a generally rectangular base panel including a generallyrectangular body of lightweight material having a rigid frame extendingsubstantially around the periphery thereof and secured thereto, twoelongated base-connecting frame members respectively disposed adjacentto opposed sides of the base panel and secured to the base panel frame,two side panels of lightweight material, the margins of the side andrespectively secured to the base-connecting frame members, fourelongated corner-connecting frame members respectively disposed adjacentto the generally upstanding margins of the side panels and securedthereto, a generally rectangular top panel of lightweight material,opposed margins of the top panel being disposed toward the adjacentmargins of the side panels and spaced therefrom, two elongated side-topconnecting frame members respectively disposed between the adjacentmargins of the side panels and the top panel and respectively securedthereto, two elongated end-top connecting frame members respectivelydisposed along the front and rear margins of the top panel and securedthereto, the front and rear portions of the base panel frame and theassociated ones of the corner connecting frame members and the end-topconnecting frame members cooperating to provide openings into thecontainer at the two ends thereof.

The invention, both as to its organization and method of operation,together with further objects and advantages thereof will best beunderstood with reference to the following specification taken inconnection with the accompanying drawings in which:

FIG. 1 is a perspective view of a container constructed in accordancewith and embodying the principles of the present invention with the doorstructure shown in the closed position;

FIG. 2 is an enlarged perspective view of the container as shown in FIG.1 with one of the door structures in the open position;

FIG. 3 is an enlarged top plan view of the container as shown in FIG. 1;

FIG. 4 is a side elevational view of the right-hand or inboard side ofthe container shown in FIG. 3;

FIG. 5 is a fragmented sectional view of an airplane fuselage showingtwo cargo containers according to the present invention in place in thecargo compartment;

FIG. 6 to FIG. 9, inclusive, are diagrammatic views of the containeraccording to the present invention, respectively showing the severalstages in moving the door structures from the closed position to thefolded stowed position thereof;

FIG. 10 is an enlarged front elevational view of the cargo containershown in FIG. 1 with the front door structure in the stowed position;

FIG. 11 is an enlarged fragmentary view of the stowed door structuretaken along the line 11-11 in FIG. 10;

FIG. 12 is a fragmentary view of the stowed door structure taken alongthe line 12-12 in FIG. 11;

FIG. 13 is a fragmentary view in partial section of the top wall frontend frame member taken along the line 13-13 in FIG. 12;

FIG. 14 is an enlarged fragmentary front elevational view of thecontainer shown in FIG. 1 with the door structure partially broken awayto show the interior of the container;

FIG. 15 is a further enlarged fragmentary view in partial section takenalong the line 15-15 in FIG. 14 and showing the door bracket assembly;

FIG. 16 is a fragmentary view in partial section of the door bracket ofFIG. 15 shown in the open position thereof;

FIG. 17 is an enlarged fragmentary sectional view of the door structuretrack members taken along the line 17-17 in FIG. 16;

FIG. 18 is a front elevational view of the door bracket assembly of FIG.15;

FIG. 19 is a side elevational view of the door bracket assembly of FIG.18 as viewed from the right-hand side thereof;

FIG. 20 is an enlarged fragmentary sectional view of the door panelslide channel taken along the line 20-20 in FIG. 14;

FIG. 21 is an enlarged fragmentary sectional view of the upper doorpanel hook member taken along the line 21-21 in FIG. 14;

FIG. 22 is an enlarged fragmentary sectional view of the lower doorpanel closeout spacer taken along the line 22-22 in FIG. 14;

FIG. 23 is an enlarged fragmentary view in partial section of the doorlatch structure taken along the line 23-23 in FIG. 14;

FIG. 24 is a fragmentary sectional view of the door panel hinge takenalong the line 24-24 in FIG. 14;

FIG. 25 is a fragmentary perspective view of one of the auxiliary framemembers showing the door latch keeper stud;

FIG. 26 is a top plan view ofa shelf for use in the container of FIG. 1;

FIG. 27 is an enlarged fragmentary view of the portion of the shelfdesignated by the numeral 27 in FIG. 26, with part of the shelf top wallbroken away to show one of the movable mounting pin assemblies;

FIG. 28 is a fragmentary view in partial section taken along the line28-28 in FIG. 27 and showing one of the fixed shelf mounting pins;

FIG. 29 is a fragmentary sectional view of the shelf spacer structuretaken along the line 29-29 in FIG. 27;

FIG. 30 is an enlarged fragmentary sectional view of one of the movableshelf mounting pin assemblies taken along the line 30-30 in FIG. 27;

FIG. 31 is a fragmentary sectional view of the shelf front edge closuremember taken along the line 31-31 in FIG. 27

FIG. 32 is an enlarged fragmentary view of the portion of the top wallof the container designated by the numeral 32 in FIG. 3;

FIG. 33 is a fragmentary sectional view of the top wall of the containertaken along the line 33-33 in FIG. 32;

FIG. 34 is a fragmentary sectional view of the union of the top andcorner frame members taken along the line 34-34 in FIG. 32;

FIG. 35 is a fragmentary view in partial section taken along the line35-35 in FIG. 10;

FIG. 36 is an enlarged fragmentary sectional view of the outboardside-base frame connecting member taken along the line 36-36 in FIG. 35;

FIG. 37 is an enlarged fragmentary sectional view of the inboardside-base connecting frame member taken along the line 37-37 in FIG. 35;

FIG. 38 is an enlarged fragmentary sectional view of the outboardside-base connecting frame member and a portion of the outboard frontcorner frame member taken along the line 38-38 in FIG. 35;

FIG. 39 is an enlarged fragmentary sectional view of the bottom wallfront closure member taken along the line 39-39 in FIG. 35.

Referring now to the drawings and particularly to FIGS. 1 and 5 thereof,there is illustrated a cargo container 50 made in accordance with andembodying the principles of the present invention. The cargo container50 is adapted for use in an aircraft, generally designated by thenumeral 60, which has the usual parts such as a fuselage 61 and wings62, with a longitudinally-extending upper deck 63 disposed slightlybelow the midline of the aircraft 60 thus to define a passengercompartment 64 in the space above the deck 63. Spaced well below thedeck 63 and extending substantially parallel thereto is a lower deck 66cooperating with the upper deck 63 and the fuselage 61 to define a cargoand/or baggage compartment 65 between the decks 63 and 66. In use, therewill preferably be provided two rows of cargo containers 50 (or baggagecontainers, as the case may be) in side-by-side relationship anddisposed along the length of the fuselage 61. As will be understood morefully hereinafter, a portion of.- one side wall in each of thecontainers 50 is slanted to more nearly conform to the outline of thefuselage 61 so that as much of the cargo compartment 65 as possible maybe utilized.

The cargo container 50 according to this invention comprises a generallybox-like structure including a substantially rectangular bottom panel100, a substantially rectangular top panel 180 disposed parallel to thebottom panel 100, and two opposed upstanding side panels and allcooperating to define a pair of door-receiving openings into thecontainer 50 at the front and rear ends thereof. Each of these openingsis closed by a foldable overhead door structure 200 for completelyclosing the container 50. One or more shelves 300 may be mounted withinthe container 50 parallel to the bottom panel 100. Throughout thisspecification, in describing the orientation of the various parts of thecontainer 50, the right-hand side as viewed in FIG. will be referred toas the inboard side, the left-hand side as viewed in FIG. 10 will bereferred to as the outboard side, the closed end as viewed in FIG. 10will be referred to as the rear end, and the open end as viewed in FIG.10 will be referred to as the front end, this terminology relating tothe orientation of the container 50 with respect to the airplane 60.

Referring now to FIGS. 1, 2, and 35 to 39, the details of constructionof the cargo container 50 will be described. The cargo container 50comprises a base panel, generally designated by the numeral 100,including a pair of spacedapart substantially rectangular sheet metalwalls 101 and 102 extending generally parallel to each other. Disposedbetween the walls 101 and 102 is a filler 103 in the form of a body ofrigid cellular construction, preferably formed of aluminum having ahoneycomb structure, the filler 103 being secured to the walls 101 and102 by means of a sheet of epoxy. Disposed between the metal walls 101and 102 at the margins thereof and extending around the periphery of thefiller 103 is a rigid frame or spacer structure, generally designated bythe numeral 105, in the form of an elongated channel having asubstantially U-shaped cross section with a bight 106 carrying a pair offlanges 107, with the bight 106 disposed inwardly of the base panel 100and abutting against the filler 103. Preferably, for the sake ofminimizing its weight and maximizing its strength and simplifying itsmanufacture, the spacer structure 105 is fonned of an aluminumextrusion. The spacer structure 105 lends rigidity to the base panel 100and, in addition, provides a means for attaching the base panel 100 toother parts of the cargo container 50 as will be described more fullyhereinafter. Disposed around the margin of the base panel 100 andextending through the walls 101 and 102 thereof and through the flanges107 of the spacer structure 105 is a plurality of holes through whichsuitable fastening means such as screws and bolts may be passed for usein connecting other parts of the cargo container 50 to the base panel100. While the opposite side edges of the base panel 100 aresubstantially parallel along most of their length, they convergeslightly at the front and rear ends thereof as at 104. Similarly, thefront and rear edges of the base panel 100 are parallel along most oftheir length, but converge slightly at the inboard and outboard endsthereof to meet the adjacent converging side edges. Thus, the corners ofthe base panel form obtuse internal angles rather than right angles asindicated for example, in FIG. 3.

There are provided along the front and rear edges of the base panel 100,base closure members, generally designated by the numeral 110, and alsopreferably formed of aluminum extrusions. The front and rear closuremembers 110 are identical in construction and, therefore, only one willbe described. Referring to FIG. 39 of the drawings, the closure member110 comprises an elongated hollow tubular member conforming in contourto the adjacent base panel edge and including a body portion 112,substantially rectangular in cross section. Extending outwardly from onewall of the body portion 112 is a pair of attachment flanges 114. Inuse, the attachment flanges 114 are inserted between the flanges 107 ofthe adjacent spacer structure 105 so that the body portion 112 of theclosure member abuts against the base panel walls 101 and 102. Theattachment flanges 114 are provided with a plurality of openingstherethrough aligned with the openings in the adjacent margin of thebase panel 100, whereby the closure member 110 may be securely fastenedto the base panel 100 by means of suitable fasteners such as screws orbolts 108. Respectively attached to the opposite ends of each of theclosure members 110 are a pair of base corner closure members 115, eachcomprising a hollow, substantially pie-shaped member adapted to fltsnugly against an adjacent end of the associated closure member and eachhaving a pair of attachment flanges 117 insertable into the body portion112 of the associated closure member 110 for attachment thereto by meansof suitable fasteners. It will be noted that the base panel walls 101and 102, the filler 103, the spacers 105, and the closure members 110and 115 are all permanently secured together to form a single base panelunit.

The outboard side panel comprises a flat substantially rectangularsheet-metal wall 121 bent to form an upwardly and outwardly slantedbottom portion 122 and a substantially vertical upstanding top portion123. There is preferably provided along the crease between the lowerportion 122 and the upper portion 123 a sheet metal bumper strip 124which is preferably riveted to the outer surface of the side panel 121.Disposed along the inner surface of the sheet-metal wall 121 is aplurality of generally upstanding stiffening frame members or ribs 125,each extending substantially the entire length of the sheet-metal wall121 and bent to conform to the contour thereof. Each of the stiffeningribs 125 comprises a tubular body portion 126 substantially rectangularin cross section and an attachment flange 127 extending outwardly fromthe body portion 126 in alignment with one wall thereof and integraltherewith. The stiffening ribs 125 are secured to the sheet-metal wall121 by means of a plurality of rivets 128 which are passed throughcomplementary openings in the sheet-metal wall 121 and the attachmentflanges 127. The forward walls of the tubular body portions 126 are eachprovided with a plurality of vertically aligned and spaced-apart holes129, the purpose of which will be explained hereinafter.

Respectively disposed along the front and rear edges of the side panelwall 121 are a pair of elongated, substantially upstanding comer framemembers 130, each of the frame members 130 extending the entire lengthof the side panel wall 121 and bent to conform to the contour thereof.The corner frame members 130 are substantially mirror images of eachother and only the front one will be described. The frame member 130includes a tubular body portion 131 substantially rectangular in crosssection and having an outboard side wall 131a and an inboard side wall131]). Integral with the body portion 131 and extending outwardlytherefrom in alignment with the outboard side wall 131a thereof is adoor-receiving flange 132, and integral with and extending from the rearwall of the body portion 131 substantially normal thereto and toward the0pposite end of the container is an attachment flange 133, each of theflanges 132 and 133 extending the entire length of the corner framemember 130. There is preferably also provided an abutment flange 132asubstantially L-shaped in cross section and extending forwardly of thebody portion 131 and outwardly toward the door-receiving flange 132. Theattachment flange 133 is offset inwardly of the body portion 131 a shortdistance substantially equal to the thickness of the side panel wall121, the adjacent margin of the side panel wall 121 overlying theattachment flange 133 and abutting against the body portion 131 of thecomer frame member 130, the outer surface of the side panel wall 121being flush with the outer surface of the outboard side wall 131a of thebody portion 131. The attachment flange 133 is secured to the overlyingmargin of the side panel wall 121 by aligned, vertically spaced openingstherethrough for receiving suitable fastening means, such as rivets, toattach the corner frame member 130 to the side panel wall 121. The upperedge of the outer side wall 131a of the comer frame member 130 carries asubstantially U-shaped notch 137a therein adjacent to the door-receivingflange 132 for a purpose which will be described hereinafter. Each ofthe corner frame members 130 is provided with a plurality of verticallyaligned spaced-apart openings 139 in the body portion 131 thereof, therear one of the corner frame members 130 having the openings 139provided in the front wall of the body portion 131 and the forward oneof the corner frame members 130 having the openings 139 provided in theinboard side wall 131b thereof, all for a purpose to be explainedhereinafter.

Attached to the bottom end of each of the corner frame members 130 is asubstantially U-shaped attachment bracket 135 having a bight 136carrying a pair of upstanding flanges 137. The flanges 137 are disposedwithin the lower end of the adjacent body portion131 of the comer framemember 130 and are respectively fastened to the, front and rear wallsthereof by means of rivets 138.

A side-base connecting frame member, generally designated by the numeral140, is provided along the bottom edge of the outboard side panel 120.The side-base connecting frame member 140 comprises an elongated tubularbody portion 142 substantially rectangular in cross section and having apair of attachment flanges 144 extending outwardly from one wall thereofsubstantially normal thereto, Integral with the body portion 142 andextending vertical upwardly therefrom is an upstanding flange 146carrying at the upper end thereof an outwardly and upwardly inclinedattachment flange 148. The attachment flange 148 overlies the bottommargin of the side panel wall 121 and is secured thereto by a pluralityof rivets 149, alternate ones of the rivets 149 preferably being alignedwith the stiffening ribs 125 and extending therethrough for securelyfastening the stiffening ribs 125, the side panel wall 121 and theside-base connecting frame member 140 together as a single structuralunit. The opposite ends of the side-base connecting frame member 140extend outwardly beyond the adjacent margins of the side panel wall 121,whereby the attachment flange 148 overlies bottom ends of the outer sidewalls 131a of the corner frame members 130 and is secured thereto bymeans of rivets.

In use, the attachment flanges 144 of the side-base connecting framemember 140 are inserted between the flanges 107 of the adjacent basepanel spacer 105 so that the outer edges of the flanges 107 and of thebase panel walls 101 and 102 abut against the body portion 142 of theside-base connecting frame member 140. A plurality of screws 108 aredisposed through complementary openings in the base panel walls 101 and102, the spacer flanges 107 and the attachment flanges 144 for securelyfastening the side-base connecting frame member 140 to the adjacent edgeof the base panel 100. The screws 108 are preferably arranged in groupsof three, with the center screw of each group of three extendingdownwardly through the top wall 101 of the base panel 100 and the otherscrews not shown) of each group of three extending upwardly through thebottom wall 102 of the base panel 100, the latter screws perferablybeing of the flathead counter-sunk variety so as to present a smoothflush surface along the bottom of the base panel 100. The screws 108 arepreferably engaged in corresponding nuts 145 which are permanentlyattached to the inner surfaces of the attachment flanges 144 of theside-base connecting frame member 140. The U-shaped attachment bracket135 is disposed closely adjacent to the inner surface of the upstandingflange 146 of the side-base connecting frame member 140, with the bight136 disposed upon and parallel to the adjacent margin of the base panelwall 101. Suitable fasteners such as bolts 108a are disposed incomplementary openings in the bight 136, the base panel wall 101, thespacer flange 107 and the attachment flange 144 and are engaged withnuts 145 attached to the inner surface of the attachment flange 144 forsecurely joining together the attachment bracket 135, the base panel 100and the side-base connecting frame member 140.

The inboard side panel, generally designated by the numeral 150,comprises a flat upstanding substantially rectangular sheet-metal wall151 disposed substantially parallel to the upper portion 123 of theoutboard side panel wall 121. Disposed along the inner surface of thesheet-metal wall 151 is a plurality of elongated upstanding stifieningframe members or ribs 155, each extending substantially the entirelength of the sheet-metal wall 151. Each of the stiffening ribs 155comprises a tubular body portion 156 substantially rectangular in crosssection and an attachment flange 157 extending outwardly from the bodyportion 156 in alignment with one wall thereof and integral therewith.The stiffening frame members 155 are secured to the sheet-metal wall 151by means of a plurality of rivets 158 which are passed throughcomplementary openings in the sheet-metal wall 151 and the attachmentflanges 157. The forward walls of the tubular body portions 156 are eachprovided with a plurality of vertically aligned and spaced-apart holes159, the purpose of which will be explained hereinafter.

Respectively disposed along the front and rear margins of the side panelwall 151 are a pair of elongated upstanding corner frame members 160,each of the corner frame members 160 extending the entire length of theside panel wall 151. The corner frame members 160 are mirror images ofeach other and only the front one will be described. The corner framemember 160 comprises a tubular body portion 161 quadrangular in crosssection with an inboard side wall 161a disposed substantially parallelto the adjacent angled corner edges 104 of the base panel and anoutboard side wall 161b substantially parallel to the side panel wall151. integral with the inboard wall 161a of the body portion 161 andextending outwardly therefrom in alignment therewith is a doorreceivingflange 162, and integral with and extending outwardly from the rear wallof the body portion 161 substantially parallel to the outboard side wall161!) thereof is an attachment flange 163, each of the flanges 162 and163 extending vertically the entire length of the corner frame member160. There is also preferably provided an abutment flange 162a,substantially L-shaped in cross section, and similar in structure to theabutment flange 132a on the corner frame member and disposed asindicated in FIG. 27. The attachment flange 163 is offset inwardly ofthe inboard side wall 161a a short distance substantially equal to thethickness of the side panel wall 151, the adjacent margin of the sidepanel wall 151 overlying the attachment flange 163 and abutting againstthe inboard side wall 161a of the corner frame member 160, the outersurface of the side panel wall 151 being flush with the outer surface ofthe wall 161a of the comer frame member 160. The attachment flanges 163and the overlying margins of the side panel wall 151 have a plurality ofaligned, vertically spaced openings therethrough for receiving suitablefastening means, preferably rivets, to attach the corner frame membersto the side panel wall 151'. The upper edge of the inboard side wall161a of the corner frame member 160 carries a substantially U-shapednotch 167a therein adjacent to the door-receiving flange 162 for apurpose to be described hereinafter. Each of the corner frame members160 is provided with a plurality of vertically aligned spaced-apartopenings 169 in the body portion 161 thereof, the rear one of the cornerframe members 160 having the openings 169 provided in the front wall ofthe body portion 161, and the forward one of the corner frame members160 having the openings 169 provided in the outboard side wall 161b ofthe body portion 161, all for a purpose to be explained hereinafter. Thelower ends of the body portions 161 of each of the corner frame members160 has the inboard side wall 161a thereof cut away to form a recess orshoulder 166, the purpose of which will be explained hereinafter.

A side-base connecting frame member, generally designated by the numeral170, is provided along the bottom edge of the inboard side panel 150,the side-base connecting frame member 170 comprising an elongatedtubular body portion 172 substantially rectangular in cross section andhaving a pair of attachment flanges 174 extending outwardly from onewall thereof substantially normal thereto. Integral with the bodyportion 172 and extending vertically upwardly therefrom is an upstandingflange 176 carrying at the upper end thereof a support flange 177extending outwardly therefrom substantially normal thereto. lntegralwith the outer end of the support flange 177 and extending upwardlytherefrom substantially normal thereto is an attachment flange 179. Thesidebase connecting frame member 170 is disposed in use directly beneaththe bottom edge of the side panel 150, with the bottom edges of the sidepanel wall 151 and the stiffening frame members 155 resting upon thesupport flange 177 and with the shoulder portions 166 of the cornerframe members 160 seated upon the support flange 177 and against theupstanding flange 176. ln this position, the attachment flange 178overlies the outer surface of the bottom margin of the side panel wall151 and is secured thereto by a plurality of rivets 179 which are passedthrough complementary aligned openings in the attachment flange 178,alternate ones of the rivets 179 preferably being aligned with thestiffening ribs 155 and extending therethrough for securely fasteningthe side panel wall 151 and the stiffening ribs 155 and the comer framemembers together as a single structural unit.

in use, the attachment flanges 174 on the side-base connecting framemember 170 are inserted between the flanges 107 of the adjacent basepanel spacer 105 so that the outer edges of the flanges 107 and the basepanel walls 101 and 102 abut against the body portion 172 of theside-base connecting frame member 170 to form flush surfaces therewith.A plurality of screws 108 are disposed through complementaryopenings inthe base panel walls 101 and 102, the spacer flanges 107 and theattachment flanges 174 for securely fastening the side-base connectingframe member 170 to the adjacent edges of the base panel 100. The screws108 are preferably arranged in groups of three in the same manner asdescribed with respect to the side-base connecting frame member 140,above, and are similarly engaged in corresponding nuts as describedabove.

The body portions 142 and 172 of the side-base connecting frame members140 and 170 respectively each have the opposite ends thereof abuttingagainst the adjacent comer closure members 115 and cooperate therewithand with the closure members 110 to form a continuous tubular bumperstrip extending around the periphery of the base panel 100 to protectthe base panel 100 and to assist in mounting the cargo container 50 inan aircraft as will be described more fully hereinafter. The outersurfaces of the closure members 110 and 115 and body portions 142 and172 of the side-base connecting frame members 140 and 170 are allsubstantially identical in cross section so as to present a continuousflush outer surface for the bumper strip around the base panel 100.

Respectively disposed along the upper margins of the side panels 120 and150 are a pair of side-top right-angle frame members 165 each comprisinga pair of legs 165a and 165b, the leg 165a being longer than the leg165b and extending a short distance beyond the opposite ends thereof. Inuse, the leg 165a is attached to the upper margin of the adjacent sidepanel wall along the outer surface thereof by a plurality ofhorizontally aligned rivets 168, with the leg 165b disposed a shortdistance above the upper edge of the adjacent side panel wall andextending inwardly thereof.

The side-top right-angle frame members 165 extend substantially theentire length of the side panel walls 121 and 151 between the associatedcorner frame members 130 or 160, with the ends of the legs 165a abuttingagainst the body portions 131 or 161 of the associated corner framemembers and with the ends of the legs 165b respectively abutting againstthe inner ends of the attachment flanges 133 or 163 of the comer framemembers.

Referring now to FIGS. 3 and 32 to 34 of the drawings, the top panel 180of the container 50 will be described hereinafter. The top panel 180comprises a flat substantially rectangular sheet-metal wall 181 disposedsubstantially parallel to the bottom panel 100. The opposite sidemargins of the top panel wall 181 respectively overlie the flanges 165bof the angle frame members 165 and are respectively spaced therefrom bya pair of flat, elongated edge bars 182. The top panel wall 181 issecurely fastened to the angle frame members 165 by a plurality offastening means 183 which extend through complementary aligned openingsthrough the margins of the top panel wall 181, the edge bars 182 and theangle frame member flanges 165b. Preferably, the fastening means 183 maycomprise screws or bolts engageable with nuts on the inner surface ofthe angle member flanges 165b. A plurality of elongated stiffening framemembers 185 are provided along the inner surface of the top panel wall181, the stiffening frame members 185 extending substantially parallelto the side panels 120 and 150 from the front edge to the rear edge ofthe top panel wall 181. Each of the stiffening frame members 185comprises an elongated channel, the cross section of which includes aU-shaped central portion 186, a pair of side flanges 187 respectivelyextending outwardly from the sides of the U- shaped portion 186 andrespectively carrying at the outer edges thereof a pair of upturnedflanges 188, the stiffening frame members 185 being disposed in use withthe bight of the U-shaped portion 186 abutting against the inner surfaceof the top panel wall 181 and secured thereto by rivets 189.

. Respectively disposed along the front and rear edges of the top panelwall 181 are a pair of end-top frame members, generally designated bythe numeral 190, and each extending the entire length of the top panelwall 181 from the side panel wall 121 to the side panel wall 151. Eachof the end-top frame members 190 comprises an elongated tubular bodyportion 191 substantially rectangular in cross section. Integral withthe body portion 191 and extending outwardly from the rear wall thereofsubstantially normal thereto is an attachment flange 193. The adjacentmargin of the top panel wall 181 overlaps the attachment flange 193 withthe edge of the top panel wall 181 abutting against the body portion 191and with the outer surface of the top panel wall. 181 being flush withthe top outer surface 192 of the body portion 191. The top panel wall181 is preferably secured to the attachment flanges 193 by a pluralityof rivets 194. The top front corner of the body portion 191 is providedwith a substantially U-shaped abutment flange 195, with the bight of theU being integral with the upper edge of the forward wall of the bodyportion 191, one flange of the 11" extending upwardly toward and beingintegral with the top wall 192 of the body portion 191 and the otherflange of the U" extending upwardly and outwardly beyond the front wallof the body portion 191. The end-top frame member 190 is disposed in useabove the upper ends of the adjacent comer frame members and 160.Referring to FIG. 34 of the drawing, the upper end of the inner portionof the corner frame member 131 is cut away, whereby the outer side wall131a extends upwardly beyond the inner side wall 131b. Similarly, thebottom wall of the body portion 191 of the endtop frame 190 is cut awayat the opposite ends thereof whereby the top wall of the body portion191 extends outwardly a slight distance beyond the ends of the bottomwall of the body portion 191. Thus, the frame member 190 may be disposedatop the comer frame member 130 with the bottom wall of the body portion191 resting on the upper edge of the inner side wall l31b and with theend of the top wall of body portion 191 resting upon the upper edge ofthe outer side wall 1310. In this position, the opposite ends of theU-shaped flange 195 will respectively rest in the notches 137a and 167ain the corner frame members 130 and 160. A right-angle attachmentbracket 196 is provided at the outer ends of the endtop frame member190, the angle bracket 196 having a horizontal flange 197 overlying thebottom wall of the body portion 191 and attached thereto by rivets 197aand a downwardly vertically extending flange 198 abutting against theinner surface of the outer side wall 131a parallel thereto. The flange198 is secured to the outer side wall 131a by suitable fastening meanssuch as screws or bolts. In like manner, the inboard ends (not shown) ofthe top frame members 190 is secured to the corner frame members byidentical attachment brackets 196.

A pair of gusset plates 152 are respectively provided at the uppercorners of the container 50 at each end thereof. Referring, for example,to FIGS. 2 and 12 of the drawings, each of the gusset plates 152 issubstantially triangular in outline having one leg thereof overlying theforward wall of the adjacent comer frame member 130 or 160 and securedthereto by three rivets 154. Another leg of the gusset plate 152 issecured to the forward wall of the end-top frame by means of threescrews or bolts 207. At the upper corner of each of the gusset plates152 between the attachment legs thereof is a recess or notch 152a, thepurpose of which will be described hereinafter. At the bottom end ofeach of the corner frame members 130 is provided another pair of gussetplates 153, also generally triangular in outline. One of the gussetplates 153 of each pair has one edge thereof overlying the front wall ofthe body portion 131 of the adjacent corner frame member 130substantially parallel thereto and secured thereto by means of aplurality of rivets. The other one of each pair of the gusset plates 153has one edge thereof overlying the rear wall of the body portion 131 ofthe adjacent comer frame member 130 substantially parallel thereto andsecured thereto by means of a plurality of rivets.

It will be noted that the side panel wall 121, the corner frame members130, the side-base connecting frame member 140, the adjacent one of theside-top right-angle frame members 165, the gusset plates 153 and theadjacent one of the gusset plates 152 are all permanently rivetedtogether into a single outboard side panel unit. Similarly, the sidepanel wall 151, the corner frame members 160, the side-base connectingframe member 170, the adjacent one of the side-top rightangle framemembers 165 and the adjacent ones of the gusset plates 152 are allpermanently riveted together into a single inboard side panel unit. Inlike manner, the top panel wall 181 is permanently riveted to thestiffening frame members 185 and the end-top connecting frame members190 to form a single top panel unit.

The container 50 is also provided with a pair of auxiliary reinforcingframe members 201 and 202, the frame member 201 being disposed adjacentto the forward end of the container 50 and the frame member 202 beingdisposed at the rear end thereof. Each of the frame members 201 and 202comprises an elongated upstanding tubular member substantiallyrectangular in cross section. The bottom end of each of the framemembers 201 and 202 is disposed between the adjacent pair of gussetplates 153 and is secured thereto by suitable fastening means such asscrews or bolts 207. At the upper ends of each of the frame members 201and 202 there is provided a generally triangular gusset plate 203attached to the outer wall thereof by means of screws or bolts, theupper edge of each of the gusset plates 203 respectively overlying theouter walls of the adjacent end-top frame members 190 and securedthereto by screws or bolts. The auxiliary frame member 201 is providedalong the inboard side thereof (righthand side as viewed in FIGS. 2 and12) with a plurality of vertically aligned and spaced-apart openings 208and the auxiliary frame member 202 is similarly provided along theforward wall thereof with a plurality of vertically aligned spaced-apartopenings 209. Preferably, the openings 208 are equal in number to theopenings 209 and to the openings 129, 139, 159 and 169 in the otherframe members, with corresponding ones of the openings in the variousframe members being in horizontal alignment with each other. The forwardwall of the auxiliary frame member 201 and the forward wall of the frontone of the corner frame members 160 are each provided with a smallcushion 206 preferably formed of a resilient material such as spongerubber. Similarly, identical cushions (not shown) are provided on therear walls of the frame members 202 and the rear one of the framemembers 160.

When assembled, the front ones of the frame members 130, 160 and 190cooperate with each other and with the front edge of the base panel 100to define a front access opening into the container 50. Similarly, therear ones of the frame members 130, 160 and 190 cooperate with eachother and with the rear edge of the base panel 100 to define a rearaccess opening into the container 50. These access openings arerespectively closed by a pair of door structures or assemblies, eachgenerally designated by the numeral 200 and being mirror images of eachother, wherefore only one of these door assemblies will be described indetail.

Referring now to FIGS. to 25 of the drawings, a pair of door bracketassemblies, generally designated by the numeral 210, are respectivelyprovided on the end-top frame members 190 adjacent to the opposite endsthereof. Since the door bracket assemblies 210 are mirror images of eachother only the outboard one will be described in detail. Each of thedoor bracket assemblies 210 includes a mounting block 211 disposed onthe inner surface of the top wall of the body portion 191 and is securedthereto by a screw 212. The outboard side of the mounting block 211 hasa recessed portion 213 at the front end thereof in which is mounted apivot pin 214. A generally U-shaped pivot member 215 is mounted on thepivot pin 214, the pivot member 215 having a bight 215a and a flange 216and a pair of eyelets 217, the pivot pin 214 being disposed through theeyelets 217 for pivotal mounting thereof. Connected to the flange 216 ofthe pivot member 215 is a slide or track member, generally designated bythe numeral 220, the slide member 220 comprising an angle bracket 221having an elongated arm 224 and a short attachment arm 222 connected tothe flange 216 of the pivot member 215 by means of rivets 223. Mountedon the outer surface of the arm 224 and substantially coterminoustherewith is a solid rail 225 substantially T-shaped in cross sectionhaving a stem 226 and a cross bar 227. The rail 225 is attached tothearm 224 by means of a plurality of screws 228 extending therethroughand through the stem 226 and being engageable with nuts 229 recessed inthe outer surface of the cross bar 227.

The door bracket assembly 220 has a normal closed position as shown inFIG. 15 wherein the arm 224 extends vertically downwardly from the pivotmember 215, the pivot member 215 and the attachment flange 222 of theangle bracket 221 being disposed within the body portion 191 of theend-top frame member 190, an opening 191a being provided in the frontwall of the body portion 191 for this purpose, access to the opening1910 being provided by the notch 152a in the gusset plate 152. In thisposition, the bight 215a of the pivot member 215 is disposed generallyrearwardly with the flange 216 and the eyelets 217 being disposedgenerally forwardly thereof, as is shown in FIG. 15. From the closedposition illustrated in FIG. 15, the door bracket assembly 220 may bepivotally moved counterclockwise as viewed in FIG. 15 on the pivot pin214 to an open position wherein the elongated arm 224 is disposedsubstantially parallel to the top panel wall 181 as illustrated in FIG.16. In the open position shown in FIG. 16, the pivot member 215 is incontact with the lower surface of the U-shaped flange 195 on the end-topconnecting frame member 190. The complementary shapes of the flange 195and the pivot member 215 allow the flange 195 to nest snugly within thepivot member 215 when the door bracket assembly is in the open positionthereof whereby the flange 195 serves as a stop to restrain the outwardpivotal movement of the door bracket assembly 220 in the openingdirection. It will of course be understood that the inboard one of thedoor bracket assemblies 220 is similarly constructed and operates in anidentical fashion.

Slidably mounted on the door bracket assemblies 220 is an upper doorpanel, generally designated by the numeral 230, and comprising a pair offlat substantially rectangular sheetmetal walls 231 and 232 extendinggenerally parallel to each other and dimensioned to completely cover theupper portion of the adjacent access opening into the container 50.Disposed between the walls 321 and 232 is a filler 233 in the form of abody of rigid cellular construction preferably formed of aluminum havinga honeycomb structure, the filler 233 being secured to the walls 231 and232 by means of a sheet of epoxy (see FIGS. 23 and 24). Disposed betweenthe walls 231 and 232 at the margins thereof and extending around theperiphery of the filler 233 is a rigid frame or spacer structure,generally designated by the numeral 235, in the form of an elongatedchannel having a substantially U shaped cross section with a bight 236carrying a pair of flanges 237, with the bight 236 disposed inwardly ofthe door panel 230 and abutting against the filler 233. The spacerstructure 235 is substantially similar in construction and function tothe spacer structure in the base panel 100.

Respectively disposed along the inboard and outboard edges of the upperdoor panel 230 and extending the length thereof is a pair of elongatedslide or track channels, generally designated by the numeral 240, andbeing minor images of each other, wherefore only the outboard one willbe described in detail. Referring to FIG. 20 of the drawings, the slidechannel 240 has a body portion generally C-shaped in cross section andincluding a bight 241 and a pair of side flanges 242, each of the sideflanges 242 being integral at one end thereof with the bight 241 andcarrying at the other end thereof a short retaining flange 243, theretaining flanges 243 extending toward each other and substantiallyparallel to the bight 241. The inboard one of the side flanges 242 isprovided with a pair of attachment flanges 248 extending therefromsubstantially normal thereto. In use, the attachment flanges 248 areinserted between the flanges 237 of the adjacent spacer 235 so that theadjacent edges of the flanges 237 and of the door panel walls 231 and232 abut against the slide channel inboard side flange 242, with theouter surfaces of the walls 231 and 232 respectively being flush withthe outer surfaces of the bight 241 and the inboard retaining flange 243of the slide channel 240. The slide channels 240 are each secured to theadjacent edge of the door panel 230 by means of a plurality of rivetsextending through the door panel walls 231 and 232, the spacer flanges237 and the side channel attachment flanges 248. Disposed through theouter one of the side flanges 242 adjacent to the lower end of each ofthe slide channels 240 is a stop pin 244, the function of which will bedescribed hereinafter. It will be understood that the inboard one of theslide channels 240 is suitably constructed.

Disposed along the upper edge of the upper door panel 230 is a hook orsupport member 245 extending along the entire length of the door panel230 from the inboard edge to the outboard edge thereof. Referring toFIG. 21 of the drawings, the hook member 245 includes a body portion 246having a generally inverted-U-shaped neck or hook 247 integral with anextending upwardly from the upper surface thereof. Extending downwardlyfrom the lower surface of the body portion 246 is a pair of attachmentlegs or flanges 249 disposed in use between the flanges 237 of theadjacent door panel spacer 235, with the upper edges of the spacerflanges 237 and the door panel walls 231 and 232 abutting against thebody portion 246 of the hook member 245. The hook member 245 is securedto the adjacent edge of the door panel 230 by means of a plurality ofrivets which are passed through the door panel walls 231 and 232, thespacer flanges 237 and the hook member attachment flanges 249. It shouldbe noted that the hook member 245 does not have the cross section shownin FIG. 21 along the entire length thereof. While the body portion 246and hook member 247 extend the entire length of the door panel 230 andoverlie the top edges of the slide channels 240, the attachment flanges249 extend only as far as the inner ends of the attachment flanges 248on the slide channels 240.

As can be seen from FIGS. 15 to 17, the slide channels 240 are eachshaped complementary to the rails 225 on the door bracket assemblies 220and are adapted to be fitted thereover for slidable engagementtherewith. Thus, the upper door panel 230 may be slidably moved alongthe cooperating slide or truck members 225 and 240 between an extendedcondition as shown in phantom in FIG. 11 and a retracted condition asshown in solid lines in FIG. 1 1 all as will be described furtherhereinafter. Sliding movement of the door panel 230 in the retractingdirection is limited by the engagement of the stop pins 244 in the slidechannels 240 with the lower ends of the rails 225 as indicated in FIG.11. Sliding movement of the door panel 230 in the extending direction islimited by engagement by the hook 247 with the slide bracket 221 whenthe door bracket assembly 220 is in the fully opened position as shownin FIG. 16 or by engagement of the hook 247 in the U- shaped flange 195when door bracket assembly 220 is in the closed position as shown inFIG. 15.

It is a significant feature of this invention, that when the doorbracket assemblies 220 are in the open positions thereof the elongatedarms 224 and the attached rails 225 are disposed a short distance abovethe top panel wall 181 and substantially parallel thereto. Thus, whenthe door bracket assemblies 220 are in the open positions thereof, themovement of the upper door panel 230 in the retracting direction alongthe track members 225 and 240 will serve to slide the top door panel 230into a position overlying the top panel 180 substantially parallelthereto for convenient stowage of the door panel 230 to facilitateloading and unloading of the container 50. For this purpose, thedimensions of the door bracket assemblies 220 are such that the verticaldistance between the top panel wall 181 and the elongated arm 224 in theopen position of the door bracket assemblies 220 is just sufficient toallow free movement of the door panel 230 above the top panel 180.

There is also provided a lower door panel, generally designated by thenumeral 250, and conforming in outline to the lower portion of theadjacent access opening into the container 50. The lower door panel 250includes a pair of spacedapart flat sheet-metal walls 251 and 252extending generally parallel to each other. Disposed between the walls251 and 252 is a filler 253 in the form of a body of rigid cellularconstruction, preferably formed of aluminum having a honeycombstructure, the filler 253 being secured to the walls 251 and 252 bymeans of a sheet of epoxy (see FIGS. 23 and 24). Disposed between themetal walls 251 and 252 along the upper margin thereof is a rigid frameor spacer structure generally designated by the numeral 255 in the formof an elongated channel having a substantially U-shaped cross sectionwith a bight 256 carrying a pair of flanges 257, the bight 256 beingdisposed inwardly of the door panel 250 and abutting against the upperedge of the filler 253. The spacer structure 255 is substantially thesame in construction and function as the spacer 235 in the upper doorpanel 230. Disposed between the metal walls 251 and 252 along the sideand bottom margins thereof is a tubular spacer structure 254substantially rectangular in cross section. The spacer 254 is insertedbetween the walls 251 and 252 with one end thereof abutting against thefiller 253 and the opposite end thereof being flush with the adjacentedges of the walls 251 and 252. The spacer 254 is secured to the doorpanel 250 by means of a plurality of rivets. There is provided along thebottom margin of the lower door panel 250 a plurality of retaining tabs257, each comprising a thin strip of metal secured to the bottom panelwalls 251 and 252 by means of screws or bolts 258 and extendingdownwardly beyond the bottom edge of the door panel 250 and respectivelyengageable in the slots 109 in the base panel as will be described morefully hereinafter.

The upper end of the lower door panel 250 is pivotally connected to thelower end of the upper door panel 230 by means of a hinge structure,generally designated by the numeral 260, and being of the piano-hingevariety. The hinge structure 260, comprises a hinge pin 261 on which arepivotally mounted a pair of hinge plates 262. Each of the hinge plates262 includes a pivot leg 263 having at one end thereof a foot portion264, the foot portion 264 carrying a pair of attachment flanges 265extending outwardly therefrom. At the other end of each of the pivotlegs 263 is a plurality of eyelets 269. In use, the eyelets 269 on eachof the hinge plates 262 are aligned with each other with the hinge pin261 disposed therethrough for providing pivotal movement of the hingeplates 262 with respect to each other. The attachment flanges 265 of oneof the hinge plates 262 is inserted between the flanges 237 on thespacer 235 of the upper door panel 230 while the attachment flanges 265of the other of the hinge plates 262 is inserted between the flanges 257of the spacer 255 of the bottom door panel 250. The door panels 230 and250 are respectively secured to the associated ones of the hinge plates262 by means of a plurality of bolts 266 extending through theassociated door panel walls, spacer flanges, and hinge plate attachmentflanges and engaging with nuts 267 on the inner surfaces of the doorpanels. While the lower one of the hinge plates 262 extends the entirelength of the upper margin of the door panel 250, the upper one of thedoor hinge plates 262 extends only as far as the inner ends of the slidechannels 240 on the upper door panel 230 as can be seen from FIG. 14.

1. In a container having a top wall and a bottom wall and a pair ofopposed side walls all cooperating to define a door-receiving opeNing, adoor structure comprising a door bracket pivotally mounted on thecontainer adjacent to the door-receiving opening, and a door panelshaped complementary to the opening and slidably mounted on said doorbracket and movable between an extended condition and a retractedcondition thereon, said door bracket being movable between a closedposition wherein said door panel is disposed within the door-receivingopening and substantially normal to an adjacent wall of the containerand an open position wherein said door panel is disposed outside of thecontainer and substantially parallel to the adjacent wall thereof, saiddoor structure having a closed position wherein said door bracket is inthe closed position thereof and said door panel is in the extendedcondition thereof whereby said door structure completely closes thedoor-receiving opening, said door structure having a stowed positionwherein said door bracket is in the open position thereof and said doorpanel is in the retracted condition thereof whereby said door structureis completely removed from the doorreceiving opening and said door panelis stowed alongside the adjacent one of the container wallssubstantially parallel thereto.
 2. The door structure set forth in claim1, wherein said door structure includes a pair of said door bracketspivotable about a common axis and respectively disposed adjacent toopposite edges of said door panel.
 3. The door structure set forth inclaim 1, wherein said door bracket is mounted on the top wall of thecontainer, whereby said door panel is stowed above the top wall of thecontainer when said door structure is in the stowed configurationthereof.
 4. The door structure set forth in claim 1, wherein said doorpanel is spaced only a short distance from the adjacent wall of thecontainer when said door structure is in the stowed position thereof,whereby the clearance required alongside the adjacent wall for stowingsaid door structure is only slightly greater than the thickness of saiddoor panel.
 5. The door structure set forth in claim 1, wherein saiddoor panel includes a pair of spaced-apart substantially parallel wallsand a body of rigid cellular construction disposed therebetween andspacer structure extending therearound for providing a strong yetlightweight construction for said door panel.
 6. The door structure setforth in claim 1, wherein one of said side walls has an upper portionextending generally parallel to the other of said side walls and a lowerportion extending inwardly from said first portion toward the other ofsaid side walls and said bottom wall.
 7. In a container having a topwall and a bottom wall and a pair of opposed side walls all cooperatingto define a door-receiving opening, a door structure comprising a doorbracket pivotally mounted on the container adjacent to thedoor-receiving opening and having a first track member thereon, and adoor panel shaped complementary to the door-receiving opening and havinga second track member thereon cooperating with said first track memberfor slidably mounting said door panel on said door bracket for slidingmovement between an extended condition and a retracted condition, saiddoor bracket being movable between a closed position wherein said doorpanel is disposed within the door-receiving opening and substantiallynormal to an adjacent wall of the container and an open position whereinsaid door panel is disposed outside of the container and substantiallyparallel to the adjacent wall thereof, said door structure having aclosed position wherein said door bracket is in the closed positionthereof and said door panel is in the extended condition thereof wherebysaid door structure completely closes the door-receiving opening, saiddoor structure having a stowed position wherein said door bracket is inthe open position thereof and said door panel is in the retractedcondition thereof whereby said door structure is completely removed fromthe door-receiving opening and said door panel is stOwed alongside theadjacent one of the container walls substantially parallel thereto. 8.The door structure set forth in claim 7, wherein said first track memberis substantially T-shaped in cross section, and said second track membercomprises a channel shaped member complementary to said first trackmember, said first track member being disposed within said second trackmember for slidably mounting said door panel on said door bracket. 9.The door structure set forth in claim 7, wherein said door structureincludes a pair of said door brackets pivotable about a common axis andrespectively disposed adjacent to opposite edges of said door panel, anda pair of second track members on said door panel respectively disposedalong the opposite edges thereof for cooperation with said pair of doorbrackets.
 10. In a container having a top wall and a bottom wall and apair of opposed side walls all cooperating to define a door-receivingopening, a door structure comprising a door bracket pivotally mounted onthe container adjacent to the door-receiving opening and having a firsttrack member thereon, a door panel shaped complementary to thedoor-receiving opening and having a second track member thereoncooperating with said first track member for slidably mounting said doorpanel on said door bracket for sliding movement between an extendedcondition and a retracted condition, said door bracket being movablebetween a closed position wherein said door panel is disposed within thedoor-receiving opening and substantially normal to an adjacent wall ofthe container and an open position wherein said door panel is disposedoutside of the container and substantially parallel to the adjacent wallthereof, and an abutment flange carried by the adjacent one of thecontainer walls and disposed adjacent to the opening and contacting saiddoor bracket in the open position thereof for limiting the pivotalmovement thereof in the opening direction, said door structure having aclosed position wherein said door bracket is in the closed positionthereof and said door panel is in the extended condition thereof wherebysaid door structure completely closes the door-receiving opening, saiddoor structure having a stowed position wherein said door bracket is inthe open position thereof and said door panel is in the retractedcondition thereof whereby said door structure is completely removed fromthe door-receiving opening and said door panel is stowed alongside theadjacent one of the container walls substantially parallel thereto. 11.The door structure set forth in claim 10, wherein said door bracketincludes a pivot member shaped complementary to said abutment flange andpivotally mounted adjacent thereto, said flange nesting within saidpivot member when said door bracket is in the open position thereof. 12.The door structure set forth in claim 10, wherein said door bracket ismounted on the top wall of the container.
 13. In a container having atop wall and a bottom wall and a pair of opposed side walls allcooperating to define a door-receiving opening, a door structurecomprising a door bracket pivotally mounted on the container adjacent tothe door-receiving opening and having a first track member thereon, adoor panel shaped complementary to the door-receiving opening and havinga second track member thereon cooperating with said first track memberfor slidably mounting said door panel on said door bracket for slidingmovement between an extended condition and a retracted condition, saiddoor bracket being movable between a closed position wherein said doorpanel is disposed within the door-receiving opening and substantiallynormal to the top wall of the container and an open position whereinsaid door panel is disposed above the top wall of the containersubstantially parallel thereto, an abutment flange substantiallyU-shaped in cross section and carried by the top wall adjacent to theopening and contacting said door bracket in the open position thereofFor limiting the pivotal movement thereof in the opening direction, anda hook member carried by said door panel adjacent to said top wall andengageable in said abutment flange when said door bracket is in theclosed position thereof and said door panel is in the extended conditionthereof for supporting said door panel and limiting the sliding movementthereof in the extending direction, said door structure having a closedposition wherein said door bracket is in the closed position thereof andsaid door panel is in the extended condition thereof whereby said doorstructure is supported by said abutment flange and completely closes thedoor-receiving opening, said door structure having a stowed positionwherein said door bracket is in the open position thereof and said doorpanel is in the retracted condition thereof whereby said door structureis completely removed from the door-receiving opening and said doorpanel is stowed above the top wall of the container substantiallyparallel thereto.
 14. The door structure set forth in claim 13, whereinsaid hook member is mounted along the upper edge of said door panel. 15.The door structure set forth in claim 13, wherein said hook member isattached to the upper edge of said door panel and extends inwardlytherefrom toward the container, whereby said hook member overlaps saidabutment flange for engagement therein when said door structure is inthe closed position thereof.
 16. The door structure set forth in claim13, and further including a stop member carried by said second trackmember adjacent to the lower end thereof, said stop member engaging saidfirst track member when said door panel is in the retracted conditionthereof for limiting the sliding movement thereof in the retractingdirection.
 17. The door structure set forth in claim 13, wherein saidhook member abuts against said door bracket when said door panel is inthe extended condition thereof and said door bracket is out of theclosed position thereof for limiting the sliding movement of said doorpanel in the extending direction.
 18. In a container having a top walland a bottom wall and a pair of opposed side walls all cooperating todefine a door-receiving opening, a door structure comprising a doorbracket pivotally mounted on the container adjacent to thedoor-receiving opening, a door panel shaped complementary to the openingand slidably mounted on said door bracket and movable between anextended condition and a retracted condition thereon, said door bracketbeing movable between a closed position wherein said door panel isdisposed within the door-receiving opening and substantially normal toan adjacent wall of the container and an open position wherein said doorpanel is disposed outside of the container and substantially parallel tothe adjacent wall thereof, said door structure having a closed positionwherein said door bracket is in the closed position thereof and saiddoor panel is in the extended condition thereof whereby said doorstructure completely closes the door-receiving opening, said doorstructure having a stowed position wherein said door bracket is in theopen position thereof and said door panel is in the retracted conditionthereof whereby said door structure is completely removed from thedoor-receiving opening and said door panel is stowed alongside theadjacent one of the container walls substantially parallel thereto, aretaining member carried by said door panel and engageable with thecontainer when said door structure is in the closed position thereof forpreventing pivotal movement thereof, and resilient latch structurecarried by said door panel and engageable with said container forholding said door panel in the extended condition thereof to hold saidretaining member in engagement with the container, whereby saidretaining member cooperates with said latch structure to hold said doorstructure in the closed position thereof.
 19. The door structure setforth in claim 18, wherein said door structure includes a plurality ofsaid retaining members carried by said door panel.
 20. The doorstructure set forth in claim 18, wherein said door bracket is mounted onthe top wall of the container, and said retaining member is disposedadjacent to the bottom edge of said door panel and is engageable with acomplementary opening in the bottom wall of the container.
 21. In acontainer having a top wall and a bottom wall and a pair of opposed sidewalls all cooperating to define a door-receiving opening, a doorstructure comprising a door bracket pivotally mounted on the containeradjacent to the door-receiving opening, a door panel shapedcomplementary to the opening and slidably mounted on said door bracketand movable between an extended condition and a retracted conditionthereon, said door bracket being movable between a closed positionwherein said door panel is disposed within the door-receiving openingand substantially normal to an adjacent wall of the container and anopen position wherein said door panel is disposed outside of thecontainer and substantially parallel to the adjacent wall thereof, saiddoor structure having a closed position wherein said door bracket is inthe closed position thereof and said door panel is in the extendedcondition thereof whereby said door structure completely closes thedoor-receiving opening, said door structure having a stowed positionwherein said door bracket is in the open position thereof and said doorpanel is in the retracted condition thereof whereby said door structureis completely removed from the door-receiving opening and said doorpanel is stowed alongside the adjacent one of the container wallssubstantially parallel thereto, a retaining member carried by said doorpanel and engageable with the container when said door structure is inthe closed position thereof for preventing pivotal movement thereof,keeper structure mounted on the container and extending through acomplementary opening in said door panel when said door structure is inthe closed position thereof to maintain said door panel in the extendedcondition thereof, and a latch mechanism resiliently mounted on theouter surface of said door panel and movable into and out of engagementwith said keeper structure when said door structure is in the closedposition thereof, whereby said retaining member cooperates with saidkeeper structure and said latch mechanism to lock said door structure inthe closed position thereof, and whereby said door structure may bequickly and easily latched and unlatched by appropriate tensioning anduntensioning of said resilient latch mounting means.
 22. The doorstructure set forth in claim 21, wherein said keeper structure comprisesa stud mounted on the container and extending outwardly therefrom. 23.The door structure set forth in claim 21, wherein said latch mechanismincludes, an elastic mounting strap attached at one end thereof to saiddoor panel, and a latch member attached to the other end of saidmounting strap.
 24. The door structure set forth in claim 21, whereinsaid keeper structure comprises a stud having an enlarged head at oneend thereof and mounted at the other end thereof on said container, saidlatch mechanism including a latch member having a keyhole-shaped openingtherein for receiving the head portion of said stud therethrough. 25.The door structure set forth in claim 21, wherein said door structureincludes two keeper structures mounted on the container, and two latchmechanisms respectively cooperating with said keeper structures forlocking said door panel in the extended condition thereof.
 26. In acontainer having a top wall and a bottom wall and a pair of opposed sidewalls all cooperating to define a door-receiving opening, a doorstructure comprising a door bracket pivotally mounted on the containeradjacent to the door-receiving opening, a first door panel shapedcomplementary to a portion of the door-receiving opening and slidablymounted on said door bracket and movable betWeen an extended conditionand retracted condition thereon, said door bracket being movable betweena closed position wherein said first door panel is disposed within thedoor-receiving opening and substantially normal to an adjacent wall ofthe container and an open position wherein said first door panel isdisposed outside of the container and substantially parallel to theadjacent wall thereof, and a second door panel shaped complementary tothe remaining portion of the door-receiving opening and hingedlyconnected to said first door panel and being pivotally movable between afirst position substantially in alignment with said first door panel anda second position overlying said first door panel and substantiallyparallel thereto, said door structure having a closed position whereinsaid door bracket is in the closed position thereof and said first doorpanel is in the extended condition thereof and said second door panel isin the first position thereof whereby said door structure completelycloses the door-receiving opening, said door structure having a foldedstowed position wherein said door bracket is in the open positionthereof and said first door panel is in the retracted condition thereofand said second door panel is in the second position thereof wherebysaid door structure is completely removed from the door-receivingopening and said door panels are stowed alongside the adjacent one ofthe container walls substantially parallel thereto.
 27. The doorstructure set forth in claim 26, wherein said door structure includes apair of said door brackets pivotable about a common axis andrespectively disposed adjacent to opposite edges of said first doorpanel.
 28. The door structure set forth in claim 26, wherein said doorbracket is mounted on the top wall of the container and said first doorpanel is disposed in the upper portion of the door-receiving opening andsaid second door panel is disposed in the lower portion of thedoor-receiving opening when said door structure is in the closedposition thereof.
 29. The door structure set forth in claim 26, whereinsaid door bracket is mounted on the top wall of the container, saidfirst door panel being disposed in the upper portion of saiddoor-receiving opening when said door structure is in the closedposition thereof, and said first door panel being hingedly connectedalong the lower margin thereof to said second door panel.
 30. The doorstructure set forth in claim 26, wherein said first door panel isdisposed only a slight distance from the adjacent one of said containerwalls when said door structure is in the stowed position thereof,whereby the clearance required alongside the adjacent wall for stowingsaid folded door structure is slightly greater than the combinedthicknesses of said panel.
 31. In a container having a top wall and abottom wall and a pair of opposed side walls all cooperating to define adoor-receiving opening, a door structure comprising a door bracketpivotally mounted on the container adjacent to the door-receivingopening and having a first track member thereon, a first door panelshaped complementary to a portion of the door-receiving opening andhaving a second track member thereon cooperating with said first trackmember for slidably mounting said first door panel on said door bracketfor sliding movement between an extended condition and a retractedcondition, said door bracket being movable between a closed positionwherein said first door panel is disposed within the door-receivingopening and substantially normal to the top wall of the container and anopen position wherein said first door panel is disposed above the topwall of the container substantially parallel thereto, a flangesubstantially U-shaped in cross section and carried by the top walladjacent to the opening and contacting said door bracket in the openposition thereof for limiting the pivotal movement thereof in theopening direction, a hook member carried by said first door paneladjacent to the top wall and engageable in said flange when said doorbracket is in the closed position thereof and said first door panel isin the extended condition thereof for supporting said first door paneland limiting the sliding movement thereof in the extending direction,and a second door panel shaped complementary to the remaining portion ofthe door-receiving opening and hingedly connected to said first doorpanel and being pivotally movable between a first position substantiallyin alignment with said first door panel and a second position overlyingsaid first door panel and substantially parallel thereto, said doorstructure having a closed position wherein said door bracket is in theclosed position thereof and said first door panel is in the extendedcondition thereof and said second door panel is in the first positionthereof whereby said door structure completely closes the door-receivingopening, said door structure having a folded stowed position whereinsaid door bracket is in the open position thereof and said first doorpanel is in the retracted condition thereof and said second door panelis in the second position thereof whereby said door structure iscompletely removed from the door-receiving opening and said door panelsare stowed above the top wall of the container substantially parallelthereto and to each other.
 32. In a container having a top wall and abottom wall and a pair of opposed side walls all cooperating to define adoor-receiving opening, a door structure comprising a door bracketpivotally mounted on the container adjacent to the door-receivingopening, a first door panel shaped complementary to a portion of thedoor-receiving opening and slidably mounted on said door bracket andmovable between an extended condition and retracted condition thereon,said door bracket being movable between a closed position wherein saidfirst door panel is disposed within the door-receiving opening andsubstantially normal to an adjacent wall of the container and an openposition wherein said first door panel is disposed outside of thecontainer and substantially parallel to the adjacent wall thereof, asecond door panel shaped complementary to the remaining portion of thedoor-receiving opening and hingedly connected to said first door paneland being pivotally movable between a first position substantially inalignment with said first door panel and a second position overlyingsaid first door panel and substantially parallel thereto, said doorstructure having a closed position wherein said door bracket is in theclosed position thereof and said first door panel is in the extendedcondition thereof and said second door panel is in the first positionthereof whereby said door structure completely closes the door-receivingopening, said door structure having a folded stowed position whereinsaid door bracket is in the open position thereof and said first doorpanel is in the retracted condition thereof and said second door panelis in the second position thereof whereby said door structure iscompletely removed from the door-receiving opening and said panels arestowed alongside the adjacent one of the container walls substantiallyparallel thereto, a retaining member carried by said second door paneland engageable with the container when said door structure is in theclosed position thereof for preventing pivotal movement thereof, keeperstructure mounted on the container and extending through a complementaryopening in the hinged connection between said first and second doorpanels when said door structure is in the closed position thereof forpreventing sliding movement of said first door panel, and a latchmechanism resiliently mounted on the outer surface of one of said doorpanels and movable into and out of engagement with said keeper structurewhen said door structure is in the closed position thereof for holdingsaid door structure in engagement with said keeper structure, wherebysaid retaining member cooperates with said keeper structure and saidlatcH mechanism to hold said door structure in the closed positionthereof.
 33. The door structure set forth in claim 32, wherein said doorbracket is mounted on the top wall of the container, said first doorpanel being disposed in the upper portion of the door-receiving openingand said second door panel being disposed in the lower portion of thedoor-receiving opening when said door structure is in the closedposition thereof, said retaining member being disposed adjacent to thelower edge of said second door panel and engageable with a complementaryopening in the bottom wall of the container.
 34. The door structure setforth in claim 32, wherein said latch mechanism is mounted on said firstdoor panel.
 35. A container comprising a top wall and a bottom wall anda pair of opposed side walls all cooperating to define a pair ofdoor-receiving openings at the opposite ends of the container, two doorstructures for respectively closing the door-receiving openings, each ofsaid door structures including a door bracket pivotally mounted on thecontainer adjacent to the door-receiving opening, and a door panelshaped complementary to the opening and slidably mounted on said doorbracket and movable between an extended condition and a retractedcondition thereon, each of said door brackets being movable between aclosed position wherein the associated door panel is disposed within theadjacent door-receiving opening and substantially normal to an adjacentwall of the container and an open position wherein the associated doorpanel is disposed outside of the container and substantially parallel tothe adjacent wall thereof, each of said door structures having a closedposition wherein the associated door bracket is in the closed positionthereof and the associated door panel is in the extended conditionthereof whereby said door structure completely closes the adjacentdoor-receiving opening, each of said door structures having a stowedposition wherein the associated door bracket is in the open positionthereof and the associated door panel is in the retracted conditionthereof whereby said door structure is completely removed from theadjacent door-receiving opening and said associated door panel is stowedalongside the adjacent one of the container walls substantially parallelthereto.
 36. A container comprising a generally rectangular base panelincluding a generally rectangular body of lightweight material having arigid frame extending substantially around the periphery thereof andsecured thereto, two elongated base-connecting frame members eachrespectively disposed adjacent to opposed sides of said base panel andsecured to said base panel frame, two side panels of lightweightmaterial, the margins of said side panels disposed toward said basepanel being spaced therefrom and respectively secured to saidbase-connecting frame members, four elongated corner-connecting framemembers respectively disposed adjacent to the generally upstandingmargins of said side panels and secured thereto, a generally rectangulartop panel of lightweight material, opposed margins of said top panelbeing disposed toward the adjacent margins of said side panels andspaced therefrom, two elongated side-top connecting frame membersrespectively disposed between the adjacent margins of said side panelsand said top panel and respectively secured thereto, two elongatedend-top connecting frame members respectively disposed along the frontand rear margins of said top panel and secured thereto, the front andrear portions of said base panel frame and the associated ones of saidcorner connecting frame members, said end-top connecting frame memberscooperating to provide openings into said container at the two endsthereof, and a door structure mounted on one of said panels andpivotable and slidable with respect thereto between a closed positionwherein said door completely closes one of said openings and an openposition wherein said door structure is removed from said opening andStowed parallel to the exterior surface of one of said panels bypivoting and sliding said door structure with respect to the one of saidpanels.
 37. The container set forth in claim 36, and further comprisinga second door structure pivotally mounted on the container andrespectively disposed in the other of said openings and shapedcomplementary thereto and being movable between a closed positioncompletely closing the associated opening and a stowed positioncompletely removed from the associated opening and disposed adjacent toone of said walls substantially parallel thereto.
 38. The container setforth in claim 36, wherein one of said side panels includes an upperportion extending generally parallel to the other of said side panelsand a lower portion extending from the lower end of said upper portiontoward said other side panel and toward said base panel.